title: Anion-templated assembly and magnetocaloric properties of a nanoscale {Gd38} cage versus a {Gd48} barrel.
abstract: The comprehensive study reported herein provides compelling evidence that anion templates are the main driving force in the formation of two novel nanoscale lanthanide hydroxide clusters, {Gd38(ClO4)6} (1) and {Gd48Cl2(NO3)} (2), characterized by single-crystal X-ray crystallography, infrared spectroscopy, and magnetic measurements. {Gd38(ClO4)6}, encapsulating six ClO4(-) ions, features a cage core composed of twelve vertex-sharing {Gd4} tetrahedrons and one Gd⋅⋅⋅Gd pillar. When Cl(-) and NO3(-) were incorporated in the reaction instead of ClO4(-), {Gd48Cl2(NO3)} is obtained with a barrel shape constituted by twelve vertex-sharing {Gd4} tetrahedrons and six {Gd5} pyramids. What is more, the cage-like {Gd38} can be dynamically converted into the barrel-shaped {Gd48} upon Cl(-) and NO3(-) stimulus. To our knowledge, it is the first time that the linear M-O-M' fashion and the unique μ8-ClO4(-) mode have been crystallized in pure lanthanide complex, and complex 2 represents the largest gadolinium cluster. Both of the complexes display large magnetocaloric effect in units of J kg(-1) K(-1) and mJ cm(-3) K(-1) on account of the weak antiferromagnetic exchange, the high N(Gd)/M(W) ratio (magnetic density), and the relatively compact crystal lattice (mass density).
authors.affiliation: Key Laboratory of Bioinorganic and Synthetic Chemistry of the Ministry of Education, State Key Laboratory of Optoelectronic Materials and Technologies, School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275 (P.R. China).
authors.forename: Fu-Sheng
authors.initials: FS
authors.lastname: Guo
authors.forename: Yan-Cong
authors.initials: YC
authors.lastname: Chen
authors.forename: Ling-Ling
authors.initials: LL
authors.lastname: Mao
authors.forename: Wei-Quan
authors.initials: WQ
authors.lastname: Lin
authors.forename: Ji-Dong
authors.initials: JD
authors.lastname: Leng
authors.forename: Róbert
authors.initials: R
authors.lastname: Tarasenko
authors.forename: Martin
authors.initials: M
authors.lastname: Orendáč
authors.forename: Jan
authors.initials: J
authors.lastname: Prokleška
authors.forename: Vladimír
authors.initials: V
authors.lastname: Sechovský
authors.forename: Ming-Liang
authors.initials: ML
authors.lastname: Tong
keywords: anion-templates; cluster compounds; lanthanides; magnetic properties